Gelatinization transition

Atichokudomchai, N., Varavinit, S., and Chinachoti, P. (2002). Gelatinization transitions of acid-modified tapioca starches by differential scanning calorimetry (DSC). Starch/Stdrke. 54, 296-302. 

Barley starch Gelatinization transition temperatured (°C) Enthalpy( /g)... 

Barley starch Granule size Gelatinization transition temperatures3 (°C) T Tp Tc Ranee (°C) Tc-T0 Enthalpy (AH) Cl/g) U/g)... 

Wc turn now to a more detailed consideration of how the multistranded collagen molecule is held together and stabilized in the native state, by examining the events which take place when this stabilization breaks down during the collagen —+ gelatin transition. 

Dilute Solution Studies of the Collagen —> Gelatin Transition... 

Fig. 17. The collagen — gelatin transition for various collagens, measured vis-cometrically. (From Doty and Nishihara, 1958.)...

Fig. 18. Comparison between the rate of the collagen — gelatin transition for soluble calfskin collagen at 35.9 C, measured as the fractional change in specific viscosity (solid line) and specific rotation (dotted line). (From Doty and Nishihara, 1958.)...

The interaction between proteases and their inhibitors is, at least by comparison with interactions which take place in food systems, a remarkably simple and straightforward association. Simple correlations of functional properties with different kinds of molecular forces cannot be made. It is possible, however, to illustrate the importance of protein structure and of protein—protein interactions as determinants of the functional properties of food proteins. I would like therefore to look at several food systems in which protein—protein or protein—other constituent interactions play a role and examine the relationship between functionality and protein structure in these systems. One of the simplest areas in which to examine this relationship is the well studied collagen-gelatin transition. 

In pure water, the temperature must be raised above 75°C to obtain gelatinization of the starch, as shown in Figure 10.18, which illustrates the influence both of the formic acid concentration and of the temperature on the gelatinization transition. 

Veis " describes the collagen-gelatin transition as a stepwise process involving the melting of a trihelical network to an amorphous form, followed by the sequential hydrolysis of various types of covalent bonds. 

Uses of gelatin are based on its combination of properties reversible gel-to-sol transition of aqueous solution viscosity of warm aqueous solutions abUity to act as a protective coUoid water permeabUity and insolubUity in cold water, but complete solubUity in hot water. It is also nutritious. These properties are utilized in the food, pharmaceutical, and photographic industries. In addition, gelatin forms strong, uniform, clear, moderately flexible coatings which readily sweU and absorb water and are ideal for the manufacture of photographic films and pharmaceutical capsules. 

Triethanolamine salts of alcohol sulfates form white crystals when obtained in pure form after recrystallization. At their melting point they are semisolid with gelatinous appearance and the transition is difficult to detect. Melting points, determined through thermograms obtained by differential scanning calorimetry, gave 72, 76, 80, and 86°C for dodecyl, tetradecyl, hexadecyl, and octadecyl sulfates, respectively [63]. 

The reported effect of konjac GaM on the glass transition of high-sugar/polysaccharide mixtures [242] can be utilized in sugar, hard-boiled and frozen confectionery products and might replace gelatin, which is refused by some consumers due to diet and health problems. 

In this work, an experimental study was conducted on gelatin in semi-dilute region in water solution and research the effect of temperature, pH, zeta potential, and ionic strength on hydrodynamic properties by viscometiy, in order to determine the conformational characteristic, and phase transition (Tgei). 

Olivares et al. (2006), studies performed viscometers very dilute gelatin solutions with concentrations between 10-5 and 10-3 g/cm3, where either intermolecular aggregation or intramolecular folding are possible, respectively, and the sol-gel transition is not observed. 

Figure 4 shows that the intrinsic viscosity is influenced by temperature for gelatin. Where the influence of temperature is manifested in a phase transition at 30°C, presented as a... 

Borchard W., Colfen H., Kisters D., Straatmann A. 2002. Evidence for phase transitions of aqueous gelatin gels in a centrifugal field. Progress in Colloid Polymers Science 119,101-112. 

Djabourov M., Leblond J., Papon P. Gelation of aqueos gelatin solutions. II. Rheology of the sol-gel transition. J. Phys. France 49 (1988b) 333-343. 

Djabourov M., Grillon Y., Leblond J. The sol-gel Transition in gelatin viewed by Diffusing colloidal probes. Polymer Gels and Networks 3 (1995) 407-428. 

Gelatine explosives, initiated by commercial detonators, will normally fire at the low velocity of detonation initially, although this may well build up quite quickly into the high velocity. For some applications a high velocity of detonation is essential. This can be ensured by the addition of barium sulphate, or other material with density exceeding 2-8, in a fine form. Such additives have the property of ensuring rapid transition to the high velocity of detonation. This is, for example, of particular importance when the explosive is to be fired under a hydrostatic head, as in submarine work. 

Acetic anhydride, Organic materials, Transition metals Hikita, T. et al., J. Chem. Soc. Japan, Ind. Chem. Sect., 1951, 54, 253-255 The stability ranges of mixtures of the acid, anhydride and organic materials (ethanol, gelatine) used in electropolishing were studied. Presence of transition metals (chromium, iron, nickel) increases the possibility of explosion. (This is why such mixtures must not be stored after use for etching metals.)... 

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